Rotating camera mount



Feb. 11, 1947. G. NASH ROTATING CAMERA MOUNT Filed April 22, 1943 4Sheets-Sheet l ATTORN Feb. 11, 1947. S

ROTATING CAMERA MOUNT Filed April 22, 194s 4 Sheets-Sh m Ra Y W w/J/ mmm ,A m

Feb. 11, 1947. A

ROTATING CAMERA MOUNT Filed April 22, 1943 4 Sheets-Sheet 4 INVENTOR vlified Nash a Q I MW ATTORN 8 Patented Feb. 11, 1947 ROTATING CAMERAMOUNT Alfred G. Nash, Richmond Hill, N. Y., assignor to hirclllld Cameraand Instrument Corporation, a corporation of Delaware Application April22, 1943, Serial No. 484,088

8 Claims. (CI. 88-45) This invention relates in generalto photographicapparatus, and more particularly to a mount adapted to be attached to anairplane for rotatably supporting an aerial camera.

Itisoftendesirableinmilitaryreconnaissance.

work, as well as in other types of aerial mappi to photograph terrain orspecific subjects while the airplane is traveling at a relatively hilhSpeed and at a relatively low altitude, illustratively 250 miles perhour at 300 feet above the terrain or object being photographed. Undersuch conditions, particularly in military reconnaissance, it isdesirable to employ small high speed aircraft capable of evasive actionof which heavy bombers or large observation planes are incapable.

Aerial photography, under such conditions accordingly necessitatesequipment different from that customarily used, particularly in theinstance of the shutter which must beat an extremely high speed design,and the camera should be so mounted on the airplane that its opticalaxis can be displaced as desired and so that the pilot of the airplanecan operate the camera from a position remote from its mounting. Ofcourse a mount capable of attaining these ends must be of simple andmgged construction so as to make certain reliable operation underextremely adverse conditions, in order to assure successful completionof the particular mission.

It is accordingly among the objects of this invention to provide a mountfor rotatably supporting and controlling an aerial camera which canattain the above ends, in addition to many others, in a thoroughlypractical and efficient manner. Other objects will be in part apparentand in part pointed out hereinafter.

The invention accordingly consists in the features of construction,combinations of elements, and arrangements of parts as will beexemplified in the structure to be hereinafter described, and the scopeof the application of which will be indicated in the following claims.

In the drawings, wherein I have shown one form of my invention,

Figure l is a perspective view of my moimt with the camera supportedtherein, this view also showing the remote control panel by which thecamera is positioned;

Figure 1A is a diagrammatic view of the camera mount and control panelinstalled in an airplane.

Figure 2 is a side elevation with certain Dortions broken away and otherportions shown in section, showing the mount with the camera supportedtherein;

Flgure3isanenlargedperspectivevlewofthe camera moimt, the cover beingremoved and portions broken away to show more clearly various structuralfeatures of the mount;

Figure4isawiringdiagramrorthecamera mount; and

Figure5isawiringdiagramoithecameraitself.

Similar reference characters refer to similar parts throughout thevarious views of the draws. Referring first to Figure 1, the cameramount is generally indicated at l0 and has mounted therein a cameragenerally indicated at l I, which may be of any suitable type, butpreferably has a shutter capable of high speed operation. The cameramount I0 is preferably so arranged that camera H is held in a positionapproximately 18 oil its vertical axis, so that the field of viewintercepted by a prism or mirror attachment on the end of the cameracone (described hereinbelow) extends from the horizon downwardly about36 (see Figure 2). As will be described, camera H can be rotated in ahorizontal plane through a complete circle and can be stopped andoperated at any one of a plurality of settings. This operation can beeffected by manipulation of a control panel or box generally indicatedat I2 (Figure 1) located at a remote position from the mount as, forexample, in the cockpit of the airplane (see Figure 1A) convenient tothe pilot so that the pilot can take oblique pictures fore, aft or toeither side of his line of flight. Furthermore, the operator can changethe camera from one setting to another with sufllcient rapidity tophotograph the same object from the rear that was taken in front, whiletraveling at a substantial speed at a relatively low altitude.

Mount It includes a base I3 which supports the various operatingmechanisms and, as is shown in Figure 2, is provided with an enlargedopening H through which the cone l5 of camera ll extends when the camerais secured to the mount. Base I3 is provided with a suitable number ofholes l6 (Figure 3) provided to receive bolts (not shown) or otherdevices for securing the camera mount to the airplane (not shown).

At regularly spaced points about opening I in base It (Figure 2) Iprovide supporting rollers, such as roller l1, rotatably mounted,preferably by an anti-friction bearing, on a stud ll which extendsupwardly through base II and through the roller, The roller is held onthe stud and the stud is held in the base by a nut l9 threaded on theupper end of the stud. There are referably four of these rollers 11provided,

three of which may be seen in Figure 3. These rollers H are sodimensioned as to extend inwardly of the edge of opening ll (Figure 2)and into a channel 23 formed in the bottom of a camera retaining ringgenerally indicated at 2| (see also Figures 1 and 3). Ring 2| is formedto clear the camera through its center in such a manner that the cameracone [5 is directed downwardly through opening H in base l3 so that theoptical axis of the camera is inclined from the vertical, preferably byan amount on the order of 18. To this end, ring 2| includes a circularwall 22 having a relatively low portion 22a and a higher portion 221).Wall portion 22a has integrally formed therewith an upstanding inclinedbracket 23 (Figure 2) through which is threaded a padded clamping screw23 which serves as a steady rest for the camera at a positiondiametrically opposite portion 22b of ring wall 22. This portion 22b ofthe ring wall is preferably flat, as shown in Figure 3, and has formedtherein a number of holes 25 to receive screws 26 (Figure 2) adapted tobe threadably received in the upper portion of camera cone i5, thus tosecure camera II in proper position within ring 2|. It may now be seenthat camera supporting ring 2| supports camera II in the desiredposition and is rotatably supported on base l3 of the mount by rollersI! to enable rotation of the camera about the axis of the ring. I

To the lower portion of camera cone l5 (Fig 2) is attached a suitablebracket or clamp 21 from which extends an angled support 28 in which amirror 29, for example, may be detachably held, as by a clamp 30fastened to support 28 by a screw 3|. Support 28 is preferably heldrigid in its angular position by a pair of oppositely disposed sidewalls, such as side Wall 32, extending downwardly from the side of clamp21 to the edge of support 23. Support 28,- and accordingly the plane ofmirror 23, is preferably disposed at such an angle that the field ofview intercepted by the mirror extends from the horizon downwardly by anamount on the order of 36, thus enabling the pilot to take picturesoblique from the position of the camera in the airplane.

As shown in Figure 3, supporting ring 2| has integrally formed therewithan annular boss in which are cut gear teeth 33. These teeth 33 (as shownin Figure 2) thus comprise an annular gear disposed immediately abovegroove 20, and accordingly are in a position to mesh with an idlerpinion 34 rotatabiy mounted preferably by an anti-friction bearing (notshown) on a stud shaft 35 extending upwardly through and suitablysecured in a plate or platform 36. Plate 36 is detachably secured tobase |3 (Figure 3) as by screw 31, so that the plate, together with thevarious devices secured thereto, may be installed on or detached fromthe mount base as a unit. Pinion 34 (Figure 2) meshes with a spur gear38 rotatably mounted on a stud shaft 33, also secured to and extendingupwardly from plate 33. This stud shaft also rotatably supports a gear40 which is attached in any suitable manner to spur gear 33 so that bothgears rotate together. The upper end of shaft 39 (Figure 3) is supportedin the top of a U-shaped bracket 4|, the feet of which are secured toplate 35 as by screws 42, the bracket thus surrounding gears 4: and 38and providing ample support for shaft 3 large gear (Figure 3') mesheswith a worm ear 43 fastened to or formed on a shaft 44, the

Opposite ends 0! which are attached as bysuitable flexible couplings aand b, respectively,

to the armature shafts 45 and I8 oi a pair oi. mo-

tors I1 and 43. Thus, it will appear that these 5 motors are connectedin tandem and together drive the train of gears comprising worm 3, gears43 and 23 (Figure 2) idler 3| and ring gear 33, thus to rotate ring 2|and accordingly camera II. It should also be noted that this train ofgears constitutes a substantial reduction so as to permit the use ofsmall high speed motors I1 and 43. Of course, if desired, a single motoronly may be used.

It will now appear that when motors l1 and 48 are energized theytogether drive shaft 4, and accordingly ring 2| through the reductiongear train described, so as to rotate the camera about the axis of ring2| into any of several positions as desired, all as will be described ingreater detail. Also, as will be described, it is desirable that thepilot be able to position the camera at any one of several predeterminedstations; to preclude the camera coasting beyond the selected station, Ipreferably provide a magnetic brake generally indicated at 43 in Figure3. This brake may be of any suitable type, and accordingly may comprisea braking unit 53 adapted to clamp the armature shaft 46 of motor 43when solenoid 5| of the brake is deenergized, thus precluding both ofmotors l1 and 48, and accordingly the camera, from coasting.

Still referring to Figure 3, I have provided a set of illustrativelyfour contacting strips, 52a, 52b, 52c, and 52!! attached to aninsulating block 53 which is fastened to retaining ring 2| as by screws5!. These strips are fastenedto block 53 as by rivets 55 so that theouter strips may be connected by a conductor 56. The rivets which securethe two inner strips to lock 53 are electricaliy connected as byconductors 51 and 58 to metallic contacts 59 and 60, respectively, whichcontacts are in turn electrically connected to the control circuit ofthe camera, as will appear from the following description of the wiringdiagrams 45 shown in Figures 4 and 5.

Illustratively, four contact plates, GI, 62, 63, and 63 are disposed inquadrature about camera retaining ring 2|. These plates are formed ofsuitable insulating material, and each is secured, as for example plate6|, to a pair of posts 65 extending upwardly from and secured to base 3of the camera mount. Each of these plates carries the same number, ofcontacting buttons as there are contacting strips 52. Thus, plate 6| is58 provided with buttons 6|a, Glb, Glc, and Sid, plate 62 with buttons62a, 62b, 62c, and 62d, plate 53 with buttons 63a, 63b, 63c and 63d, andplate 64 with buttons "a, Nb, 64c, and 64d. Thus, there are on each ofthese contact plates 9. set of buttons positioned to engage thecontacting strips attached to plate 53 when ring 2| is rotated throughthe several stations. As will be described hereinafter, the rotation ofring 2| is automatically controlled so that when one of 65 the contactplates M44 is selected, the ring automatically stops so as to positionthe contacting strips 5211-5241 in engagement with the contact buttonson the selected plate, as for example plate 6| in Figure 3. At the timecontact is made between the strips and buttons, ring 2| not onlyimmediately stops rotation by reason of the action of magnetic brake 43,but also a circuit is completed to the circuit in camera (Figure 1)which automatically efiects operation thereof.

With reference to Figure 3, a normally closed relay. generally indicatedat CI, is secured to molmt base II, and it is this relay which controlsthe operation of motors Cl and 48 when the control panel I! (Figure 1)is adjusted. Current is supplied to the mount circuit from the aircraftsupply at a socket ll, while control panel I! is connected to the mountcircuit by a cable I. As shown in Figure 1, the operating mechanism forthe mount is preferably housed within a detachable cover It, which isreadily removable for access to the mechanism.

The operation and control of my above-described mount can best beunderstood by reference to the wiring diagrams shown in Figures 4 and 5.As noted above, current is supplied to the mount from the aircraftsupply by socket 01. To the terminals of this socket are connected mainleads II and II across which motors 41 and ll are connected by way ofleads I2 and I3. Lead I3 is connected to a movable contact ll whichcoacts with a stationary contact I! connected by a lead It to lead ll.Thus, when contacts I4 and II are in engagement, motors 41 and 48operate. Contact ll is mounted on the armature ll of relay 86, and asthis relay is normally closed, contact 14 and 15 are normally out ofengagement. Coil 5| of magnetic brake 49 is connected across leads I1and I3 by leads l8 and I! so that when the circuit of motors 41 and I8is closed to energize the motors, brake coil Si is energized to retractbrake element 50 from the armature shaft 46 of motor 48. When, however,the motor circuit is broken by reason of the separation of contacts 14and I5, coil 5| of the magnetic brake is deenergized permitting brakespring a to force brake 50 against shaft 46, thus preventing the motorsand accordingly the camera mounting ring 2| (Figure 3) from coasting.

Referring back to Figure 3, the inside contact buttons 6ld64d areconnected in series by a wire 8. which in turn is connected to lead IIfrom the current supply. The next to the inside contact buttons tic-44care connected together by a wire" which is in turn connected by a leadD2 to a terminal C. The next to the outside set of contact buttonsBib-64b are connected together by a wire 83 which is in turn connectedby a lead 84 to a terminal G. Outside button In is connected by a wire85 to a terminal F; outside button 620 is connected by a wire 86 to aterminal E; outside button 630. is

' connected by a wire 81 to a terminal A, and outside button 64a isconnected by a wire 88 to a terminal D. This set of terminals alsoincludes terminals B and H connected respectively to main lead It and alead 89, the other end of lead 89 being connected to the coil 66a ofrelay 56. The other end or this coil is connected by a lead 90 to mainlead Ill, and hence to one side of socket 61.

Insulating block 53 is indicated diagrammatically in Figure 4, andthecontact arms carried thereby are indicated by the arrows 52a52d. Itmay be seen that the inner and outer contact strips 520 and 52d areconnected by wire 58 and thence to ground; the next to the outer strip52b is connected by a lead 9| to a post B; the next to the inside strip2c is connected by a lead 92 to a post A. Posts A and B correspond toposts A and B shown in socket 93 in Figure 5 and lead to variouselements of the camera circuit, as will be described.

Thus post B of the camera circuit is connected by a lead M to a movablearm 95 carrying a contact 90 which is normally in engagement 6withastationarycontactll connectedtoalead I. Clmtacts It and I1constitute an overrun control for the camera motors, and areautomatically separated when the supply of him in the camera magazinehas been exhausted. Inasmuch as the specific detafls of the cameracircuit and its operation comprise no part of the present invention, itwill suillce to point out that lead 00 is connected to one side ofcamera motors l9 and I II, the other sides of the motors being connectedby a lead III to ground. Post A of socket $3 is connected by a lead II:to one side of a dim wind indicator, generally indicated at I", theother side of the indicator being connected by a lead III to ground.This indicator is preferablydrivendirectlybythefllmandisso constitutedas to flash once for each cyclic operation of the camera, the indicatorpreferably being located in control box I! where it is readily visibleto the operator of the camera or the pilot of the airplane, as the casemay be, so as to indicate to him the proper operation of the camera.

Terminals A-H (Figure 4) are connectable with a complementary set ofterminals AI-HI by cable GI. Terminals Fl, AI, El, and DI connectedrespectively by leads I05, I06, I01, and III to the several controlpositions of control panel I! herein illustratively designated fore,aft, right, and left, respectively.

Control panel It includes a selector switch I (see also Figure l) whichis movable to any of the stations indicated, and this switch isconnected by a lead III to terminal HI. A camera signal light III isconnected across terminals CI and GI by leads II! and H3, respectively,while an on-oil switch I is connected to terminal Bl by a lead III, theother side of the switch being connected by a lead 6 to lead III.Preferably, camera signal light III and on-off switch Ill are located oncontrol panel I2, as shown in Figure 1, so as to be readily visible andavailable to the pilot, or to whomever is operating the camera.

Thus, assuming that on-oi! switch H4 is turned to its on" position, theoperation of the control is as follows: when the selector switch orswitch arm Ill (Figure 4) in the control panel I2 is manually rotated toa desired position such as, for example, the fore" position, a circuitis closed to energize the driving motors l1 and 48, causing the mountring II and accordingly insulating block 53 to rotate clockwise. Thiscircuit is constituted as follows: socket 61, lead II, I2, motors 41,ll, lead I3, contacts I4 and I5, and leads I6 and I0 back to the otherside of socket 61. It should be noted, however, that this circuit isenergized only when contacts I4 and I5 are closed, and these contactsare closed only when relay 56 is deenergized. This relay is energizedonly when selector switch I09 is in one of the control panel positionsindicated and when contact strips Flo-52d are in engagement with one ofthe sets of contact buttons, for example, set filo-Sid. Thus, forexample, when the contact strips are in engagement with that set ofbuttons, and selector switch II! is at the fore" position, the followingcircuit is completed: switch arm I09, lead IIII, terminals HI and H,lead 89, relay 66, lead and lead III to one side of socket 61; the otherside of socket 61, lead H, wire 80, contact button Sid. contact strip52d, conductor 56, contact strip 520, contact button Bla, lead 8!,terminals F and PI, lead I05 to the "fore station, and thus back toselector arm I09. This circuit, however, is broken when switch arm mightbe made in the I09 is moved from the fore station and accordingly relaycoil 66a is deenergized, permitting contacts 14 and 15 to close, thus toenergize the motor circuit. The motors then operate to retate mount ring2| and accordingly contact Strips 52o52d to the position selected, andwhen the strips engage the contact buttons at the selected station, thecircuit 'to relay coil 66a is reconstituted and motor control contactsI4 and 15 are separated, thus breaking the circuit to the operatingmotors 41 and 48. when these contacts separate, the circuit to magneticbrake 49 is also broken, permitting brake spring 49a to press brake shoeagainst the armature shaft 46 thus immediately stopping motors l1 and 48and accordingly preventing mount ring 2! from coasting beyond thedesired position.

When contact strips 5241-5211 engage with a set of contact buttons, forexample buttons i|a 6 Id, the camera circuit shown in Figure 5 isconnected to the current supply. This circuit is constituted as follows:socket 61, lead", terminals B, Bl, lead H5, on-ofi' switch Ill, lead H6,lead 3, camera signal light II I, lead 2, terminals CI and C, lead 82,contact button 20, wire II, button ilc, contact strip 52c, lead 52, postA, film wind indicator I03 and lead I to ground, lead 55 (Figure 4),contact button Gld, wire 80 and lead H to the other side of socket 61,thus energizing the film wind indicator circuit. The energizing circuitfor camera motors 99 and Hill is constituted as follows: socket 61, leadHI, terminals B and BI, lead H5, on-01f switch Ill, lead 6, lead H3,terminals GI and G, lead 84, wire 83, contact button ilb, contact strip52b, lead 9|, post B, lead 94 (Figure 5), lead 85, contacts 95 and 91,lead 98, motors 9s and "Ill, lead III to ground, wire 56, contact strip5211, contact button 6| d, wire 80 and lead H to the other side ofsupply socket 61.

Thus engagement of contact strips 5211-4211 with buttons film-6| denergizes the camera circuits which control the camera motors and thefilm wind indicator. In this connection, it should be notedthat-filmwind indicator I" includes a cam I030 adapted to be rotated by the himin the camera magazine. Thus when the unexposed film is exhausted, thecircuit through the film wind indicator is automatically broken and asthe camera signal light I (Figure 4,) is in this circuit, it cannotlight, thus indicating to the operator or pilot either that the film isexhausted or is otherwise unavailable for exposure.

Furthermore, the outside contact buttons filo- 64a and the insidebuttons i|dild in conjunction respectively with contact strips 520 and52d control the position of the camera.

It will thus be seen that the camera can be operated at will wheneverthe mount is stationed at one of the four positions, but that it willnot operate, even when switch Ill (Figure 4) is on, while the mount isrotating (except when it passes over a setof contact buttons on its wayaround to the selected set). If desired, a solenoid operated counter orthe. like (not shown) may be substituted'tor magazine signal light I inorder to provide the operator with an actual record of the number ofexposures taken or remaining in the camera.

Thus I have provided a camera mount which attains the several objectshereinabove set forth in a thoroughly practical and eflicient manner.

As many possible embodiments may be made of the above invention, and asmany changes embodiment above set 8 forth, it is to be understood thatall matter here inbei'ore set forth or shown in the accompanyingdrawings is to be interpreted as illustrative and not in a limitingsense.

I claim:

1. In photographic apparatus, the combination of, a rotatable support, acamera mounted on said support so as to rotate therewith, a motor fordriving said support, a motor for operating said camera, a supportmotorcontrol circuit, a camera motor circuit. a plurality of angularly spacedstationary contacts in each of said circuits. a plurality of movablecontacts in said circuits and movable into and out of engagement withsaid stationary contacts uponoperatlon of said support motor to rotatesaid support, said support motor control circuit being so arranged as toeflfect deenergization 01' said support motor when its stationary andmovable contacts are engaged and to efl'ect energimtion of said supportmotor when said contacts are disengaged, said camera motor circuit beingoppomtely arranged. a second set of contacts asociated with said supportmotor control circuit and angularly spaced in accordance with thearrangement of said first-mentioned stationary contacts, the location ofthese stationary contacts being in accordance with different selectablepredetermined operative angular positions of the support, a switch armasociated with said second set of contacts, means mounting said switcharm and said second set of contacts for relative motion therebetween,means connected to said switch arm and responsive to disengagementthereof from any of said second set of contacts for eilectingenergization of said support motor control circuit thereby to eil'ectrotation of said support, and means associated with said support andresponsive to rotation thereof into that position which is in accordancewith the position of that one of said second set of contacts previouslyengaged by said switch arm for simultaneously deenergizing gaged by saidmovable contact during or said support, said control circuit being soarranged as to efiect deenergization of said support motor circuit whenits stationary and movable contacts are engaged and to eflfectenerglzation of said support motor mentioned stationary contacts, thelocation of these stationary contacts being in accordance with diflerentselectable p edetermined operative angular positions 01' the support, aswitch including a circuit adapted rotation circuit when said contactsarm associated with said second set of contacts. means mounting saidswitch arm and said second set of contacts for relative motiontherebetween, and means connected to said switch arm and responsive todisengagement thereof from any of said second set of contacts foreflecting deenergization of said control circuit thereby to effectenergization of said support motor circuit and rotation of said support,said control circuit being energized only when said stationary andmovable contacts are engaged and said switch arm engages one of saidsecond set of contacts, whereby said control circuit may be deenergizedby disengaging said arm from said one of the second set of contacts,said control circuit being reenergized only when said switch arm hasbeen moved to a selected one of said second set or contacts and saidmovable contacts have been brought into engagement with that group orstationary contacts corresponding to the selected one of said second setof contacts.

3. In photographic apparatus, the combination of, a rotatable support, acamera mounted on said support so as to rotate therewith, a motor fordriving said support, a motor for operating said camera, a support motorcircuit, a camera motor circuit, control means including a circuitadapted when energized to effect deenerglzation of said support motorcircuit and when deenergized to effect energization of said supportmotor circuit, a plurality of stationary contacts in said control andcamera motor circuits, a plurality of movable contacts in said controland camera motor circuits and movable into and out of engagement withsaid stationary contacts upon operation of said support motor to rotatesaid support, said stationary contacts being arranged in angularlyspaced groups so as to be successively engaged by said movable contactsduring rotation of said support, said control circuit being so arrangedas to effect deenerglzation of said support motor circuit when itsstationary and movable contacts are engaged and to efiect energizationof said support motor circuit when said contacts are disengaged, saidcamera motor circuit being oppositely arranged, a second set of contactsincluded in said control circuit and angularly spaced in accordance withthe arrangement of said firstmentioned stationary contacts, the locationor these stationary contacts being in accordance with difierentselectable predetermined operative angular positions of the support, aswitch arm associated with said second set of contacts, means mountingsaid switch arm and said second set of contacts for relative motiontherebetween, means connected to said switch arm and responsive todisengagement thereof from any of said second set of contacts foreffecting deenerglzation of said control circuit thereby to eflectenerglzation of said support motor circuit and rotation of said support,said control circuit being energized only when said stationary andmovable contacts are engaged and said switch arm engages one of saidsecond set of contacts, whereby said control circuit may be deenergizedby disengaging said arm from said one of the second set of contacts,said control circuit being reenergized only when said switch arm hasbeen moved to a selected one of said second set of contacts and saidmovable contacts have been brought into engagement with that group ofstationary contacts corresponding to the selected one of said second setof contacts, and means responsive to energization of said controlcircuit ior preventing said sup- 10 port from after deenerglzation ofsaid support motor circuit- 4. Apparatus according to claim 1 whereinthe stationary contacts are arranged in groups equidistantly positionedaround the axis of rotation of said supportjthe positions of said groupscoinciding with predetermined selectable positions of operation of saidcamera.

5. Apparatus according to claim 2 wherein the control means for the spport motor circuit ineludes a solenoid and a switch operated thereby,said solenoid being in said control circuit and said switch being insaid motor circuit, said switch adapted to open upon energization ofsaid soleacid.

6. In apparatus of the character described, the combination of, anairplane, a base unit mounted in said airplane in a position remote fromthe cockpit thereof and inaccessible to the pilot during flight, asupport rotatably mounted on said base unit, a camera mounted on saidsupport so as to rotate therewith, a support motor, a camera motor, acircuit for energizing said support motor, a circuit for energizing saidcamera motor, means for simultaneously deenergizing said support motorcircuit and energizing said camera motor circuit, whereby rotation ofthe support and camera is stopped and operation of the camera iseii'ected, switch means movable to any one of a plurality of positionsand electrically associated with said first-mentioned means and locatedin the cockpit of the airplane accessible to the pilot for actuatingsaid first-mentioned means to stop rotation of said support andaccordingly of said camera and to start said camera motor, meansaccessible to the pilot for simultaneously starting the support motorand stopping the camera motor, and means associated with saiddust-mentioned means and with said switch means for stopping saidsupport in any one of a plurality of selectable positions as determinedby selective positioning of said switch means.

'7. In apparatus of the character described, the combination of, anairplane, a base unit mounted in said airplane in a position remote fromthe cockpit thereof and inaccessible to the pilot during flight, asupport rotatably mounted on said base unit, a camera mounted on saidsupport so as to rotate therewith, a motor for driving said support, amotor for operating said camera, a support motor circuit, a camera motorcircuit, a plurality of angularly spaced stationary contacts in each ofsaid circuits, a plurality of movable contacts in said circuits andmovable into and out of engagement with said stationary contacts uponoperation or said suppo t motor to rotate said support, said supportmotor control circuit being so arranged as to eflfect deenerglzation ofsaid support motor when its stationary and movable contacts are engagedand to eflect energization of said support motor when said contacts aredisengaged, said camera motor circuit being oppositely arranged, asecond set of contacts associated with said support motor controlcircuit and angularly spaced in accordance with the arrangement of saidfirst-mentioned stationary contacts, the location or these stationarycontacts being in accordance with diiierent selectable predeterminedoperative angular positions of the support, a switch arm associated withsaid second set of contacts, said switch arm and said second set ofcontacts being located in the cockpit of the airplane and accessible tothe pilot, means mounting said switch arm and said second set ofcontacts for relative motion there- 11 between, means connected to saidswitch arm and responsive to disengagement thereof from any of saidsecond set of contacts for eifecting energization of said supp rt motorcontrol circuit thereby to eflect rotation of said support, and meansassociated with said support and responsive to rotation thereof intothat position which is in accordance with the position of that one Ofsaid second set of contacts previously engaged by said switch arm forsimultaneously deenergizing said support motor control circuit andenergizing said camera motor circuit.

8. In apparatus of the character described, the combination of, anairplane, a base unit mounted in said airplane in a position remot fromthe cockpit thereof and inaccessible to the pilot during flight, asupport rotatably mounted on said base unit, a camera mounted on saidsupport so as to rotate therewith, a motor for driving said support, amotor for operating said camera, a support motor circuit, a camera motorcircuit,

control means including a circuit adapted when energized to eifectdeenergization of said support motor circuit and when deenergized toefiect energization of said support motor circuit, a plurality ofstationary contacts in said control and camera motor circuits, aplurality of movable contacts in said control and camera motor circuitsand movable into and out of engagement with said stationary contactsupon operation of said support motor to rotate said support, saidstationary contacts being arranged in angularly spaced groups so as tobe successively engaged by said movable contacts during rotation of saidsupport said control circuit being so arranged as to effectdeenergization of said support motor when its stationary and movablecontacts are engaged and to eflectenergization of said support motorwhen" said contacts are disengaged, said camera motor circuit beingoppositely arranged, a second set of contacts included in said controlcircuit and angularly spaced in accordanc with the arrangement of saidfirstmentioned stationary contacts, the location of these stationarycontacts being in accordance with diflferent selectable predeterminedoperative angular positions of the support, a switch arm associated withsaid second set of contacts, said second set of contacts together withsaid switch arm being located in the cockpit of the airplane accessibleto the pilot, means mounting said switch arm and said second set ofcontacts for relative motion therebetween, and means connected to saidswitch arm and responsive .to disengagement thereof from any of saidsecond set of contacts for effecting deenergization of said controlcircuit, thereby to effect energization of said motor circuit andaccordingly rotation of said support, said control circuit beingenergized only when said stationary and movable contacts are engaged andsaid switch arm engages one of said second set of contacts, whereby saidcontrol circuit may be deenergized by disengaging said arm from said oneof the second set of con- .tacts, said control circuit being reenergizedonly when said switch arm has been moved to a selected one of saidsecond set of contacts and said movable contacts have been brought intoengagement with that group of stationary contacts corresponding to theselected one of said second set of contacts.

ALFRED G. NASH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,829,142 Hyden Oct. 27, 19311,510,527 Rothe Oct. 7, 1924 2,180,639 McMahon, et al. Nov. 21, 19391,423,364 Sharpe July 18, 1922

